Complementary metal oxide semiconductor (CMOS) is an integrated circuit technology offering low power consumption, ease of circuit design, and increasingly high performance with device scaling. Bipolar complementary metal oxide semiconductor (BiCMOS) is an integrated circuit technology that combines bipolar devices with CMOS to yield integrated circuit devices that can have reduced noise, improved linearity, device matching, and high drive capacity, and permit improved performance. BiCMOS integrated circuits have bipolar and MOS transistors formed on the same semiconductor body or substrate. One significant advantage of such devices is that they combine the high power and fast switching speeds of bipolar devices with the high density and low power consumption of MOS transistors. The diversity of uses for such BiCMOS devices has fueled a surge toward fabricating faster, denser and more powerful integrated BiCMOS devices by more individual device enhancing manufacturing processes.
When forming devices using a BiCMOS manufacturing process, care is taken to mitigate the number of masks employed therein to lower the manufacturing costs. Therefore efforts are made as often as is practicable to integrate the use of regions typically utilized for CMOS devices as regions in a bipolar device, and vice-versa. While such integration does serve to minimize manufacturing costs, in some cases the integration causes performance tradeoffs to be made.
One problem that can result from this integration is forming BiCMOS devices without tailoring specific characteristics, such as breakdown voltage due to the integration. The integration can, for example, prevent adjustment of dopant concentrations for various regions of the devices. As a result, the devices are formed with operational and/or performance characteristics that cannot be tailored.